1. Technical Field
The present invention relates generally to a camera calibration apparatus and method using parallelograms in each image and multi-view control, and, more particularly, to a camera calibration apparatus and method using parallelograms located on respective surfaces which are different from each other within each image.
2. Description of the Related Art
Generally, a camera calibration operation has been widely used in computer vision, robotics, the movie industry, and human-computer interaction, in which 3D information is generated using cameras.
An example of such a camera calibration method is to perform camera calibration using a specifically manufactured camera frame. As described above, when a calibration frame is used, the relative position of a specific marker can be previously and accurately known, so that accurate results can be obtained. However, there is the inconvenience of always having to carry a heavy and large calibration frame.
As another example, various continuous images are captured, so that the images themselves are used to perform camera calibration. Like this, a method of calibrating images based on projective geometric restoration is called automatic calibration, and can be used on the assumption that the parts of camera internal variables are known. Calibration can be performed even though there is no geometric information about a specific calibration frame or background. However, there is a problem in that a large amount of images are required for accuracy.
As another further example, camera calibration is performed using geometric information existing on images. Here, the geometric information existing on images may include a set of parallel lines at a vertical direction, spheres, and circles. When such geometric information is used, camera calibration can be performed without using a specific calibration frame and a plurality of images. However, there is a problem in that camera calibration cannot be performed when geometric information, such as a set of parallel lines at a vertical direction, spheres and circles, does not exist.
In order to solve such a problem, there is a camera calibration method using parallelograms which frequently appear on artificial structures. However, there is a problem of decreasing accuracy because infinite topographies for each pair of cameras should be calculated separately.